Radio-frequency module and communication device

ABSTRACT

A radio frequency module includes a module board including a first principal surface and a second principal surface on opposite sides thereof; a transmission power amplifier; a control circuit configured to control the transmission power amplifier; a first transmission filter and a second transmission filter; and a first switch configured to switch connection of an output terminal of the transmission power amplifier between the first transmission filter and the second transmission filter. The control circuit is disposed on the first principal surface, and the first switch is disposed on the second principal surface.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is based on and claims priority of JapanesePatent Application No. 2019-171568 filed on Sep. 20, 2019 and JapanesePatent Application No. 2020-057972 filed on Mar. 27, 2020. The entiredisclosures of the above-identified applications, including thespecification, drawings and claims are incorporated herein by referencein their entirety.

TECHNICAL FIELD

The present disclosure relates to a radio frequency module and acommunication device.

BACKGROUND

In mobile communication apparatuses such as a mobile phone thearrangement configuration of circuit elements included in radiofrequency (RF) front-end circuits is becoming complex, particularly withdevelopments in multiband technologies.

Japanese Unexamined Patent Application Publication No. 2018-181943discloses a power amplifying module including power amplifiers in anoutput stage and a driver stage, matching circuits provided at a frontstage, a mid-stage, and a back stage to the power amplifiers, a switchfor selectively connecting the power amplifiers to any of a plurality oftransmission paths, and a control circuit that controls the operation ofthe power amplifiers. According to this configuration, it is possible toensure sufficient isolation between the input and output signals of thepower amplifier.

SUMMARY Technical Problem

However, as recognized by the present inventor, when the poweramplifying module described in Japanese Unexamined Patent ApplicationPublication No. 2018-181943 is included, as a transmission circuit, in asmall transceiver module, there are cases where a digital control signaloutput from the control circuit that controls a power amplifier causesgeneration of a spurious signal in the adjacent channel of thetransmission signal that passes the power amplifier and a switch.Consequently, there is the issue that the adjacent channel leakage ratio(ACLR) of the transmission signal deteriorates, and thus transmissionsignal quality deteriorates.

The present disclosure provides a radio frequency module that suppressestransmission signal quality deterioration and a communication deviceincluding the radio frequency module.

Solutions

A radio frequency module according to an aspect of the presentdisclosure includes a module board including a first principal surfaceand a second principal surface on opposite sides of the module board; atransmission power amplifier disposed on the module board; a controlcircuit configured to control the transmission power amplifier; a firsttransmission filter and a second transmission filter; and a first switchconfigured to switch connection of an output terminal of thetransmission power amplifier between the first transmission filter andthe second transmission filter, wherein the control circuit is disposedon the first principal surface, and the first switch is disposed on thesecond principal surface.

Advantageous Effects

The present disclosure is capable of providing a radio frequency moduleand a communication device that suppress deterioration of transmissionsignal quality.

BRIEF DESCRIPTION OF DRAWINGS

These and other advantages and features will become apparent from thefollowing description thereof taken in conjunction with the accompanyingDrawings, by way of non-limiting examples of embodiments disclosedherein.

FIG. 1 is a circuit configuration diagram of a radio frequency module(or RF front-end circuitry) and a communication device according to anembodiment.

FIG. 2A is a schematic diagram illustrating a plan view configuration ofa radio frequency module according to a Working Example 1.

FIG. 2B is a schematic diagram illustrating a cross-sectionalconfiguration of the radio frequency module according to the WorkingExample 1.

FIG. 2C is a schematic diagram illustrating a plan view configuration ofa radio frequency module according to Variation 1.

FIG. 3A is a schematic diagram illustrating a plan view configuration ofa radio frequency module according to a Working Example 2.

FIG. 3B is a schematic diagram illustrating a cross-sectionalconfiguration of the radio frequency module according to the WorkingExample 2.

DESCRIPTION OF EMBODIMENTS

Hereinafter, exemplary embodiments of the present disclosure will bedescribed in detail with reference to the drawings. It should be notedthat each of the subsequently described exemplary embodiments shows ageneric or a specific example. The numerical values, shapes, materials,elements, the arrangement and connection of the elements, and othersindicated in the following exemplary embodiments are mere examples, andtherefore are not intended to limit the present disclosure. Among theelements described in the following exemplary embodiments andvariations, elements not recited in any one of the independent claimsare described as optional elements. In addition, the sizes of theelements and the ratio of the sizes illustrated in the drawings are notnecessarily accurate. In the figures, elements which are substantiallythe same are given the same reference signs, and overlapping descriptionis omitted or simplified.

Furthermore, hereinafter, terms indicating a relationship betweenelements such as “parallel” and “perpendicular”, terms indicating theshape of an element such as rectangular, as well as numerical ranges arenot only expressions with strict meanings, but also expressions whosemeanings include substantially the same range, such as an error ofseveral percent, for example.

Furthermore, with regard to A, B, and C which are mounted on a board inthe subsequent description, “C is mounted between A and B in a plan viewof the board (or a principal surface of the board)” means that, in aplan view of the board, at least one of a plurality of lines connectingarbitrary points in A and arbitrary points in B passes through theregion of C. Furthermore, a plan view of the board means viewing theboard and circuit elements mounted on the board by orthographicprojection of a plane parallel to a principal plane of the board.

Furthermore, in the subsequent description, “A is disposed on a firstprincipal surface of the board” refers, not only to the state in which Ais directly mounted on the first principal surface, but also to thestate in which A is mounted in the space on the first principalsurface-side, out of the space on the first principal surface-side andthe space on the second principal surface-side which are isolated by theboard. Specifically, the above expression includes the state in which Ais mounted on the first principal surface via another circuit element,electrode, or the like.

Furthermore, in the subsequent description, “transmission path” refersto the transfer path formed by a line for transferring a radio frequencysignal, an electrode directly connected to the line, a terminal directlyconnected to the line or the electrode, and so on. Furthermore, in thesubsequent description, “reception path” refers to the transfer pathformed by a line for receiving a radio frequency signal, an electrodedirectly connected to the line, a terminal directly connected to theline or the electrode, and so on. Furthermore, “signal path” refers tothe transfer path formed by a line for transferring a radio frequencysignal, an electrode directly connected to the line, a terminal directlyconnected to the line or the electrode, and so on. Furthermore, as usedherein, the term “circuit” or “circuitry” means one or more circuits,including discrete circuit(s) as well as circuit board(s) andcombinations thereof.

Embodiment

[1. Circuit Configuration of Radio Frequency Module 1 and CommunicationDevice 5]

FIG. 1 is a circuit configuration diagram of radio frequency module 1and communication device 5 according to an embodiment. As illustrated inthe figure, communication device 5 includes radio frequency module 1,antenna 2, RF signal processing circuit (RFIC) 3, and baseband signalprocessing circuit (BBIC) 4. In this exemplary configuration, thecommunication device is a multi-band transceiver. As used in thisspecification, the term “module”, as used with “radio frequency module”,or “RF front-end module” should be construed as circuitry (programmable,as well as discrete) and associated circuit components, such as circuitboards, RF shielding, etc.

RFIC 3 is an RF signal processing circuit that processes a radiofrequency signal that is to be transmitted or has been received byantenna 2. Specifically, RFIC 3 performs, by downconversion, and so on,signal processing on a reception signal input via a reception path ofradio frequency module 1, and outputs the reception signal generated bythe signal processing to BBIC 4. Furthermore, RFIC 3 performs, byupconversion, and so on, signal processing on a transmission signalinput from BBIC 4, and outputs the transmission signal generated by thesignal processing to a transmission path of radio frequency module 1.

BBIC 4 is a circuit that performs signal processing using anintermediate frequency band having a lower frequency than a radiofrequency signal transferred in radio frequency module 1. The signalprocessed by BBIC 4 is, for example, used as an image signal for imagedisplay or as a sound signal for communication via a speaker.

Furthermore, RFIC 3 also functions as a controller that controls theconnection of switches 51, 52, 53, 54, 55, and 56 included in radiofrequency module 1, based on the communication band (frequency band) tobe used. Specifically, RFIC 3 controllably switches the connection(s) ofswitches 51 to 56 included in radio frequency module 1 according to acontrol signal (not illustrated). Specifically, RFIC 3 outputs, to PAcontrol circuit 13, digital control signals for controlling switches 51to 56. PA control circuit 13 of radio frequency module 1 controls theconnection and disconnection of switches 51 to 56 by outputting digitalcontrol signals to switches 51 to 56, according to digital controlsignals input from RFIC 3.

Furthermore, RFIC 3 also functions as a controller that controls thegain of transmission power amplifiers 11 and 12 included in radiofrequency module 1 as well as power supply voltage Vcc and bias voltageVbias supplied to transmission power amplifiers 11 and 12. Specifically,RFIC 3 outputs digital control signals such as MIPI and GPIO to controlsignal terminal 113 of radio frequency module 1. PA control circuit 13of radio frequency module 1 adjusts the gain of transmission poweramplifiers 11 and 12 by outputting control signals, power supply voltageVcc, or bias voltage Vbias to transmission power amplifiers 11 and 12,according to digital control signals input via control signal terminals113 and 114. It should be noted that the control signal terminal thatreceives, from RFIC3, the digital control signals for controlling thegain of transmission power amplifiers 11 and 12 and the control signalterminal that receives, from RFIC3, the digital control signals forcontrolling power supply voltage Vcc and bias voltage Vbias to besupplied to transmission power amplifiers 11 and 12 may be different. Itshould be noted that the controller may be provided outside RFIC 3, andmay be provided in BBIC 4, for example. Moreover, in one example, thecontroller is a remote computer, or a distributed computer system thatcommunicates with the radio frequency module 1 via a wireless or wiredconnection. Likewise, in another example, the controller is a localcontroller with a user interface that converts input signals intocontrol commands that control the communication device 5 as well assubcomponents, such as the RF module 1.

Antenna 2 is connected to antenna connection terminal 100 of radiofrequency module 1, emits radio frequency signals output from radiofrequency module 1, and receives radio frequency signals from theoutside and outputs the received radio frequency signals to radiofrequency module 1.

It should be noted that in communication device 5 according to thisembodiment, antenna 2 and BBIC 4 are not essential elements, and thus,communication device 5 may include interface ports to accommodateantenna 2 and BBIC 4 as auxiliary components.

Next, the detailed configuration of radio frequency module 1 will bedescribed.

As illustrated in FIG. 1, radio frequency module 1 includes antennaconnection terminal 100, transmission power amplifiers 11 and 12,reception low-noise amplifiers (LNAs) 21 and 22, PA control circuit 13,transmission filters 61T, 62T, 63T, and 64T, reception filters 61R, 62R,63R, and 64R, transmission output matching circuit 30, reception inputmatching circuit 40, matching circuits 71, 72, 73, and 74, switches 51,52, 53, 54, 55, and 56, diplexer 60, coupler 80, coupler output terminal180.

Antenna connection terminal 100 is an example of an input/outputterminal, and is an antenna common terminal connected to antenna 2.

Transmission power amplifier 11 is an amplifier that amplifies radiofrequency signals of communication band A (first communication band) andcommunication band B (second communication band) which belong to a firstfrequency band group and are input through transmission input terminal111 (input terminal). Furthermore, transmission power amplifier 12 is anamplifier that amplifies radio frequency signals of communication band Cand communication band D which belong to a second frequency band groupdifferent in frequency from the first frequency band group and are inputthrough transmission input terminal 112 (input terminal).

PA control circuit 13 is an example of a control circuit that adjuststhe gain of transmission power amplifiers 11 and 12 according to digitalcontrol signals MIPI and GPIO input via control signal terminals 113 and114. PA control circuit 13 may be formed in a first semiconductorintegrated circuit (IC). The first semiconductor IC is configured using,for example, a complementary metal oxide semiconductor (CMOS).Specifically, the first semiconductor IC is configured using a siliconon insulator (SOI) process. Accordingly, the first semiconductor IC canbe manufactured at low cost. It should be noted that the firstsemiconductor IC may be formed using at least one of GaAs, SiGe, or GaN.Accordingly, radio frequency signals having high quality amplificationperformance and noise performance can be output.

Reception low-noise amplifier 21 is an amplifier that amplifies radiofrequency signals of communication band A and communication band B withlow noise, and outputs the amplified radio frequency signals toreception output terminal 121 (output terminal). Furthermore, receptionlow-noise amplifier 22 is an amplifier that amplifies radio frequencysignals of communication band C and communication band D with low noise,and outputs the amplified radio frequency signals to reception outputterminal 122 (output terminal).

Transmission filter 61T, which is an example of a first transmissionfilter, is connected to transmission path AT connecting transmissioninput terminal 111 and antenna connection terminal 100, and passestransmission signals of the transmission band of communication band Aout of the transmission signals amplified by transmission poweramplifier 11. Furthermore, transmission filter 62T, which is an exampleof a second transmission filter, is connected to transmission path BTconnecting transmission input terminal 111 and antenna connectionterminal 100, and passes transmission signals of the transmission bandof communication band B out of the transmission signals amplified bytransmission power amplifier 11. In addition, transmission filter 63T,which is an example of a first transmission filter, is connected totransmission path CT connecting transmission input terminal 112 andantenna connection terminal 100, and passes transmission signals of thetransmission band of communication band C out of the transmissionsignals amplified by transmission power amplifier 12. Moreover,transmission filter 64T, which is an example of a second transmissionfilter, is connected to transmission path DT connecting transmissioninput terminal 112 and antenna connection terminal 100, and passestransmission signals of the transmission band of communication band Dout of the transmission signals amplified by transmission poweramplifier 12.

Reception filter 61R is connected to reception path AR connectingreception output terminal 121 and antenna connection terminal 100, andpasses reception signals of the reception band of communication band Aout of the reception signals input from antenna connection terminal 100.Furthermore, reception filter 62R is connected to reception path BRconnecting reception output terminal 121 and antenna connection terminal100, and passes reception signals of the reception band of communicationband B out of the reception signals input from antenna connectionterminal 100. In addition, reception filter 63R is connected toreception path CR connecting reception output terminal 122 and antennaconnection terminal 100, and passes reception signals of the receptionband of communication band C out of the reception signals input fromantenna connection terminal 100. Moreover, reception filter 64R isconnected to reception path DR connecting reception output terminal 122and antenna connection terminal 100, and passes reception signals of thereception band of communication band D out of the reception signalsinput from antenna connection terminal 100.

Transmission filter 61T and reception filter 61R constitute duplexer 61which has, as a passband, communication band A. Furthermore,transmission filter 62T and reception filter 62R constitute duplexer 62which has, as a passband, communication band B. In addition,transmission filter 63T and reception filter 63R constitute duplexer 63which has, as a passband, communication band C. Moreover, transmissionfilter 64T and reception filter 64R constitute duplexer 64 which has, asa passband, communication band

D

It should be noted that each of duplexers 61 to 64 may be a multiplexerconsisting of only a plurality of transmission filters, a multiplexerconsisting of only a plurality of reception filters, or a multiplexerconsisting of a plurality of duplexers.

Transmission path AT is for transferring transmission signals ofcommunication band A. One end of transmission path AT is connected toantenna connection terminal 100, and the other end of transmission pathAT is connected to transmission input terminal 111. Transmission path BTis for transferring transmission signals of communication band B. Oneend of transmission path BT is connected to antenna connection terminal100, and the other end of transmission path BT is connected totransmission input terminal 111. Transmission path CT is fortransferring transmission signals of communication band C. One end oftransmission path CT is connected to antenna connection terminal 100,and the other end of transmission path CT is connected to transmissioninput terminal 112. Transmission path DT is for transferringtransmission signals of communication band D. One end of transmissionpath DT is connected to antenna connection terminal 100, and the otherend of transmission path DT is connected to transmission input terminal112.

Reception path AR is for transferring reception signals of communicationband A. One end of reception path AR is connected to antenna connectionterminal 100, and the other end of reception path AR is connected toreception output terminal 121. Reception path BR is for transferringreception signals of communication band B. One end of reception path BRis connected to antenna connection terminal 100, and the other end ofreception path BR is connected to reception output terminal 121.Reception path CR is for transferring reception signals of communicationband C. One end of reception path CR is connected to antenna connectionterminal 100, and the other end of reception path CR is connected toreception output terminal 122. Reception path DR is for transferringreception signals of communication band D. One end of reception path DRis connected to antenna connection terminal 100, and the other end ofreception path DR is connected to reception output terminal 122.

Here, each of reception low-noise amplifier 21, the circuit elements ofmatching circuit 41, switch 53, and reception filters 61R and 62R is afirst circuit component that is connected to reception paths AR and BRfor transferring reception signals. Here, each of reception low-noiseamplifier 22, the circuit elements of matching circuit 42, switch 54,reception filters 63R and 64R is a first circuit component that isconnected to reception paths CR and DR for transferring receptionsignals. Furthermore, each of diplexer 60 and switch 55 is a firstcircuit component that is connected to reception paths AR, BR, CR, andDR for transferring reception signals.

Transmission output matching circuit 30 includes matching circuits 31and 32. Matching circuit 31 is connected to a transmission pathconnecting transmission power amplifier 11 and transmission filters 61Tand 62T, and matches impedances of transmission power amplifier 11 andtransmission filters 61T and 62T. Matching circuit 32 is connected to atransmission path connecting transmission power amplifier 12 andtransmission filters 63T and 64T, and matches impedances of transmissionpower amplifier 12 and transmission filters 63T and 64T.

Reception input matching circuit 40 includes matching circuits 41 and42. Matching circuit 41 is connected in a reception path connectingreception low-noise amplifier 21 and reception filters 61R and 62R, andmatches impedances of reception low-noise amplifier 21 and receptionfilters 61R and 62R. Matching circuit 42 is connected in a receptionpath connecting reception low-noise amplifier 22 and reception filters63R and 64R, and matches impedances of reception low-noise amplifier 22and reception filters 63R and 64R.

Switch 51, which is an example of a first switch, includes a commonterminal and two selection terminals. The common terminal of switch 51is connected to the output terminal of transmission power amplifier 11via matching circuit 31. One selection terminal of switch 51 isconnected to transmission filter 61T connected to transmission path AT,and the other selection terminal of switch 51 is connected totransmission filter 62T connected to transmission path BT In thisconnection configuration, switch 51 switches between connecting anddisconnecting the common terminal and the one selection terminal andconnecting and disconnecting the common terminal and the other selectionterminal. In other words, switch 51 switches between connecting anddisconnecting the output terminal of transmission power amplifier 11 andtransmission filter 61T and connecting and disconnecting the outputterminal of transmission power amplifier 11 and transmission filter 62T.Switch 51 is, for example, a single pole, double throw (SPDT) switchcircuit.

Switch 52, which is an example of a first switch, includes a commonterminal and two selection terminals. The common terminal of switch 52is connected to the output terminal of transmission power amplifier 12via matching circuit 32. One selection terminal of switch 52 isconnected to transmission filter 63T connected to transmission path CT,and the other selection terminal of switch 52 is connected totransmission filter 64T connected to transmission path DT In thisconnection configuration, switch 52 switches between connecting anddisconnecting the common terminal and the one selection terminal andconnecting and disconnecting the common terminal and the other selectionterminal. In other words, switch 52 switches between connecting anddisconnecting the output terminal of transmission power amplifier 12 andtransmission filter 63T and connecting and disconnecting the outputterminal of transmission power amplifier 12 and transmission filter 64T.Switch 52 is, for example, an SPDT switch circuit.

Switch 53 includes a common terminal and two selection terminals. Thecommon terminal of switch 53 is connected to the input terminal ofreception low-noise amplifier 21 via matching circuit 41. One selectionterminal of switch 53 is connected to reception filter 61R connected toreception path AR, and the other selection terminal of switch 53 isconnected to reception filter 62R connected to reception path BR. Inthis connection configuration, switch 53 switches between connecting anddisconnecting the common terminal and the one selection terminal, andconnecting and disconnecting the common terminal and the other selectionterminal. In other words, switch 53 switches between connecting anddisconnecting reception low-noise amplifier 21 and reception path AR,and switches between connecting and disconnecting reception low-noiseamplifier 21 and reception path BR. Switch 53 is, for example, an SPDTswitch circuit.

Switch 54 includes a common terminal and two selection terminals. Thecommon terminal of switch 54 is connected to the input terminal ofreception low-noise amplifier 22 via matching circuit 42. One selectionterminal of switch 54 is connected to reception filter 63R connected toreception path CR, and the other selection terminal of switch 54 isconnected to reception filter 64R connected to reception path DR. Inthis connection configuration, switch 54 switches between connecting anddisconnecting the common terminal and the one selection terminal, andconnecting and disconnecting the common terminal and the other selectionterminal. In other words, switch 54 switches between connecting anddisconnecting reception low-noise amplifier 22 and reception path CR,and switches between connecting and disconnecting reception low-noiseamplifier 22 and reception path DR. Switch 54 is, for example, an SPDTswitch circuit.

Switch 55, which is an example of an antenna switch, is connected toantenna connection terminal 100 via diplexer 60, and switches between(1) connecting and disconnecting antenna connection terminal 100 andtransmission path AT and reception path AR, (2) connecting anddisconnecting antenna connection terminal 100 and transmission path BTand reception path BR, (3) connecting and disconnecting antennaconnection terminal 100 and transmission path CT and reception path CR,and (4) connecting and disconnecting antenna connection terminal 100 andtransmission path DT and reception path DR. It should be noted thatswitch 55 is a multiple-connection switch circuit capable ofsimultaneously performing two or more connections among (1) to (4)above.

Matching circuit 71 is connected to a path connecting switch 55 andduplexer 61, and matches impedances of (i) antenna 2 and switch 55 and(ii) duplexer 61. Matching circuit 72 is connected to a path connectingswitch 55 and duplexer 62, and matches impedances of (i) antenna 2 andswitch 55 and (ii) duplexer 62. Matching circuit 73 is connected to apath connecting switch 55 and duplexer 63, and matches impedances of (i)antenna 2 and switch 55 and (ii) duplexer 63. Matching circuit 74 isconnected to a path connecting switch 55 and duplexer 64, and matchesimpedances of (i) antenna 2 and switch 55 and (ii) duplexer 64.

Diplexer 60 is an example of a multiplexer, and consists of filters 60Land 60H. Filter 60L is an example of an LC filter which includes atleast one of an inductor or a capacitor which is in chip form, and has,as a passband, a frequency range including the first frequency bandgroup and the second frequency band group. Filter 60H is an example ofan LC filter which includes at least one of an inductor or a capacitorwhich is in chip form, and has, as a passband, a frequency rangeincluding an other frequency band group different in frequency from thefirst frequency band group and the second frequency band group. Oneterminal of filter 60L and one terminal of filter 60H is connected incommon to antenna connection terminal 100. It should be noted that, whenthe first frequency band group and the second frequency band group arelocated more to the low frequency side than the other frequency bandgroup is, filter 60L may be a low-pass filter and filter 60H may be ahigh-pass filter.

Coupler 80 and switch 56 form a circuit that monitors the powerintensity of radio frequency signals transferred between antennaconnection terminal 100 and switch 55, and output the monitored powerintensity to RFIC 3 via coupler output terminal 180.

It should be noted that transmission filters 61T to 64T and receptionfilters 61R to 64R may be any of acoustic wave filters that make use ofsurface acoustic waves (SAW), acoustic wave filters that make use ofbulk acoustic waves (BAW), LC resonant filters, and dielectric filters,for example, but are not limited to these filters.

Furthermore, transmission power amplifiers 11 and 12 and receptionlow-noise amplifiers 21 and 22 are each configured using, for example, afield effect transistor (FET) or a heterojunction bipolar transistor(HBT) made of, for instance, a Si-based complementary metal oxidesemiconductor (CMOS) or GaAs.

Furthermore, reception low-noise amplifiers 21 and 22 and switches 53,54, and 55 may be formed in a second semiconductor integrated circuit(IC). In addition, the second semiconductor IC may further includetransmission power amplifiers 11 and 12 and switches 51 and 52. Thesecond semiconductor IC is configured using a CMOS, for example.Specifically, the second semiconductor IC is formed using a silicon oninsulator (SOI) process. According to this configuration, the secondsemiconductor IC can be manufactured at low cost. It should be notedthat the second semiconductor IC may be formed using at least one ofGaAs, SiGe, or GaN. Accordingly, radio frequency signals having highquality amplification performance and noise performance can be output.

It should be noted that matching circuits 71 to 74, coupler 80, switch56, and coupler output terminal 180 are not essential elements of theradio frequency module according the present disclosure.

In the configuration of radio frequency module 1 described above,transmission power amplifier 11, matching circuit 31, switch 51,transmission filter 61T, matching circuit 71, switch 55, and filter 60Lform a first transmission circuit that transfers transmission signals ofcommunication band A toward antenna connection terminal 100.Furthermore, filter 60L, switch 55, matching circuit 71, receptionfilter 61R, switch 53, matching circuit 41, and reception low-noiseamplifier 21 form a first reception circuit that transfers receptionsignals of communication band A from antenna 2 via antenna connectionterminal 100.

Furthermore, transmission power amplifier 11, matching circuit 31,switch 51, transmission filter 62T, matching circuit 72, switch 55, andfilter 60L form a second transmission circuit that transferstransmission signals of communication band B toward antenna connectionterminal 100. In addition, filter 60L, switch 55, matching circuit 72,reception filter 62R, switch 53, matching circuit 41, and receptionlow-noise amplifier 21 form a second reception circuit that transfersreception signals of communication band B from antenna 2 via antennaconnection terminal 100.

Furthermore, transmission power amplifier 12, matching circuit 32,switch 52, transmission filter 63T, matching circuit 73, switch 55, andfilter 60L form a third transmission circuit that transfers transmissionsignals of communication band C toward antenna connection terminal 100.In addition, filter 60L, switch 55, matching circuit 73, receptionfilter 63R, switch 54, matching circuit 42, and reception low-noiseamplifier 22 form a third reception circuit that transfers receptionsignals of communication band C from antenna 2 via antenna connectionterminal 100.

Furthermore, transmission power amplifier 12, matching circuit 32,switch 52, transmission filter 64T, matching circuit 74, switch 55, andfilter 60L form a fourth transmission circuit that transferstransmission signals of communication band D toward antenna connectionterminal 100. In addition, filter 60L, switch 55, matching circuit 74,reception filter 64R, switch 54, matching circuit 42, and receptionlow-noise amplifier 22 form a fourth reception circuit that transfersreception signals of communication band D from antenna 2 via antennaconnection terminal 100.

According to the above-described circuit configuration, radio frequencymodule 1 is capable of performing at least one of simultaneouslytransmitting, simultaneously receiving, or simultaneously transmittingand receiving a radio frequency signal of either communication band A orcommunication band B and a radio frequency signal of eithercommunication band C or communication band D.

It should be noted that, in the radio frequency module according to thepresent disclosure, the above-described four transmission circuits andthe above-described four reception circuits need not be connected toantenna connection terminal 100 via switch 55, and the four transmissioncircuits and the four reception circuits may be connected to antenna 2via a different terminal. Furthermore, it is sufficient that the radiofrequency module according to the present disclosure includes at leastPA control circuit 13 and at least one of the first transmissioncircuit, the second transmission circuit, the third transmissioncircuit, or the fourth transmission circuit.

Furthermore, in the radio frequency module according to the presentdisclosure, it is sufficient that the first transmission circuitincludes transmission power amplifier 11 and switch 51. In addition, itis sufficient that the second transmission circuit includes transmissionpower amplifier 11 and switch 51. Moreover, it is sufficient that thethird transmission circuit includes transmission power amplifier 12 andswitch 52. Furthermore, it is sufficient that the fourth transmissioncircuit includes transmission power amplifier 12 and switch 52.

Here, when the respective circuit elements of radio frequency module 1described above are to be mounted on a single module board as a smallfront-end circuit, it is necessary to reduce the circuit componentlayout area of the module board surface. In this case, it is assumedthat, for example, PA control circuit 13 and the transmission-relatedcircuit components connected to transmission paths AT to DT are to beplaced in close proximity. In this case, there are instances where thedigital control signal output from PA control circuit 13 causes aspurious signal to be generated in the adjacent channel of thetransmission signal. Accordingly, there is the problem that the ACLR ofthe transmission signals deteriorates, and thus transmission signalquality deteriorates.

In contrast, radio frequency module 1 according to this embodiment has aconfiguration that suppresses electric field coupling, magnetic fieldcoupling, or electromagnetic field coupling of PA control circuit 13 andthe transmission-related circuit components. The configuration of radiofrequency module 1 according to this embodiment which suppresseselectric field coupling, magnetic field coupling, or electromagneticfield coupling will be described below.

[2. Circuit Element Arrangement Configuration of Radio Frequency Module1A According to Working Example 1]

FIG. 2A is a schematic diagram illustrating a plan view configuration ofradio frequency module 1A according to Working Example 1. Furthermore,FIG. 2B is a schematic diagram illustrating a cross-sectionalconfiguration of radio frequency module 1A according to Working Example1, and specifically illustrates a cross-section taken along line IIB-IIBin FIG. 2A. It should be noted that (a) in FIG. 2A illustrates anarrangement diagram of circuit elements in the case where principalsurface 91 a of opposite principal surfaces 91 a and 91 b of moduleboard 91 is viewed from the z-axis positive direction-side. On the otherhand, (b) in FIG. 2A illustrates a see-through view of the arrangementof circuit elements in the case where principal surface 91 b is viewedfrom the z-axis positive direction-side.

Radio frequency module 1A according to Working Example 1 shows aspecific arrangement configuration of the respective circuit elementsincluded in radio frequency module 1 according to the embodiment.

As illustrated in FIG. 2A and FIG. 2B, radio frequency module 1Aaccording to the working example further includes module board and resinmaterials 92 and 93, in addition to the circuit configurationillustrated in FIG. 1.

Module board 91 has principal surface 91 a (second principal surface)and principal surface 91 b (first principal surface) on opposite sides,and is a board on which the transmission circuits and the receptioncircuits are mounted. For module board 91, for example, a lowtemperature co-fired ceramic (LTCC) board having a stacked structure ofa plurality of dielectric layers, a high temperature co-fired ceramic(HTCC) board, a component-embedded board, a board having aredistribution layer (RDL), a printed circuit board, or the like can beused. It should be noted that antenna connection terminal 100,transmission input terminals 111 and 112, and reception output terminals121 and 122 may be formed on module board 91.

Resin material 92 is disposed on principal face 91 a of module board 91,covers a portion of the transmission circuits, a portion of thereception circuits, and principal surface 91 a of module board 91, andhas a function of ensuring reliability such as the mechanical strengthand moisture resistance of the circuit elements included in thetransmission circuits and reception circuits. Resin material 93 isdisposed on principal face 91 b of module board 91, covers some of thetransmission circuits, some of the reception circuits, and principalsurface 91 b of module board 91, and has a function of ensuringreliability such as the mechanical strength and moisture resistance ofthe circuit elements included in the transmission circuits and receptioncircuits. It should be noted that resin materials 92 and 93 are notessential elements of the radio frequency module according to thepresent disclosure.

Each of matching circuits 41 and 42 includes at least a chip inductor.

As illustrated in FIG. 2A and FIG. 2B, in radio frequency module 1Aaccording to this working example, transmission power amplifiers 11 and12, duplexers 61 to 64, switches 51 and 52, and matching circuits 31,32, 41, and 42 are surface mounted on principal surface 91 a of moduleboard 91. On the other hand, PA control circuit 13, reception low-noiseamplifiers 21 and 22, switches 53, 54, and 55, and diplexer 60 aresurface mounted on principal surface 91 b of module board 91. It shouldbe noted that, although not illustrated in FIG. 2A and FIG. 2B, matchingcircuits 71 to 74 and coupler 80 may be surface mounted on either one ofprincipal surface 91 a or 91 b of module board 91, or may be embedded inmodule board 91. It should be noted that since coupler 80 monitors thepower intensity of the radio frequency signals transferred in radiofrequency module 1A and outputs the power intensity to an externalcircuit such as RFIC 3 via coupler output terminal 180, it is desirablefor coupler 80 to be mounted on principal surface 91 b on the motherboard-side.

It should be noted that, although not illustrated in FIG. 2A, the linesincluded in transmission paths AT, BT, CT, and DT and reception pathsAR, BR, CR, and DR illustrated in FIG. 1 are formed inside module board91 and on principal surfaces 91 a and 91 b. Furthermore, theaforementioned lines may be bonding wires which have both ends bonded toany of principal surfaces 91 a and 91 b and circuit elements included inradio frequency module 1A, and may be terminals, electrodes, or linesformed on the surface of the circuit elements included in radiofrequency module 1A.

In this working example, as illustrated in FIG. 2A and FIG. 2B, PAcontrol circuit 13 is disposed on principal surface 91 b, and switches51 and 52 are disposed on principal surface 91 a.

According to the above-described configuration, PA control circuit 13and switches 51 and 52 are disposed with module board 91 interposedtherebetween. Accordingly, electric field coupling, magnetic fieldcoupling, or electromagnetic field coupling of PA control circuit 13 andswitches 51 and 52 can be suppressed. For this reason, it is possible toprevent a digital control signal output from PA control circuit 13 fromcausing the generation of a spurious signal in the adjacent channel of atransmission signal which passes switches 51 and 52. Accordingly,deterioration of the ACLR of the transmission signal can be suppressed.Therefore, it is possible to provide radio frequency module 1A thatsuppresses transmission signal quality deterioration.

Furthermore, as illustrated in FIG. 2A and FIG. 2B, it is desirablethat, in a plan view of module board 91, PA control circuit 13 andswitch 51 at least partially overlap. Alternatively, it is desirablethat, in a plan view of module board 91, PA control circuit 13 andswitch 52 at least partially overlap.

PA control circuit 13 controls transmission amplifiers 11 and 12, andcontrols connection and disconnection of switches 51 and 52 by usingdigital control signals. According to the above-described configuration,since PA control circuit 13 and switch 51 or 52 partially overlap in theaforementioned plan view, the control lines connecting PA controlcircuit 13 and switch 51 or 52 can be shortened. Accordingly, it ispossible to further prevent the control signal output from PA controlcircuit 13 to switch 51 or 52 from causing the generation of a spurioussignal in the adjacent channel of the transmission signal that passesswitch 51 or 52. Accordingly, deterioration of the ACLR of thetransmission signal can be further suppressed.

In this working example, duplexers 61 to 64 and matching circuits 41 and42 are first circuit components connected to reception paths AR to DR,and are disposed on principal surface 91 a. On the other hand, PAcontrol circuit 13 is disposed on principal surface 91 b.

According to this configuration, PA control circuit 13 is disposed onprincipal surface 91 b of module board 91, and the first circuitcomponents connected to reception paths AR to DR are disposed onprincipal surface 91 a. In other words, PA control circuit 13 and thefirst circuit components are disposed with module board 91 interposedtherebetween. Accordingly, electric field coupling, magnetic fieldcoupling, or electromagnetic field coupling of PA control circuit 13 andthe first circuit components can be suppressed. For this reason, it ispossible to prevent the harmonic of a digital control signal output fromPA control circuit 13 from flowing into reception paths AR to DR.Therefore, it is possible to prevent the harmonic from flowing into anyof reception paths AR to DR and causing reception sensitivity todeteriorate.

Furthermore, as illustrated in FIG. 2A, it is desirable that, in a planview of module board 91, PA control circuit 13 and the first circuitcomponents connected to reception paths AR to DR do not overlap.Accordingly, aside from PA control circuit 13 and the first circuitcomponents being disposed with module board 91 interposed therebetween,it is possible to ensure sufficient distance between PA control circuit13 and the first circuit components, and thus electric field coupling,magnetic field coupling, or electromagnetic field coupling of PA controlcircuit 13 and the first circuit components can be further suppressed.

It should be noted that PA control circuit 13 is connected to a controlline that transfers digital control signals output from RFIC 3 and isconnected by control lines to transmission power amplifiers 11 and 12and switches 51 to 56, and is formed in a first semiconductor IC, forexample.

It should be noted that radio frequency module 1A according to thisworking example has a configuration in which PA control circuit 13 isdisposed on principal surface 91 b and duplexers 61 to 64 and matchingcircuits 41 and 42 are disposed on principal surface 91 a but is notlimited to such configuration.

In the radio frequency module according to the present disclosure, it issufficient that PA control circuit 13 be disposed on one of principalsurfaces 91 a and 91 b, and that at least one (i.e., the first circuitcomponent) of the circuit components given below is disposed on theother of principal surfaces 91 a and 91 b. Specifically, it issufficient that the first circuit component be at least one of thefollowing:

(1) Reception low-noise amplifier 21 or 22;

(2) The inductor of matching circuit 41 or the inductor or matchingcircuit 42;

(3) Switch 53 or 54;

(4) Any one of reception filters 61R to 64R or any one of duplexers 61to 64;

(5) Duplexer 60; or

(6) Switch 55.

Accordingly, compared to a radio frequency module having a configurationin which PA control circuit 13 and the circuit components in (1) to (6)above are disposed on the same principal surface, electric fieldcoupling, magnetic field coupling, or electromagnetic field coupling ofPA control circuit 13 and the at least one of (1) to (6) above can besuppressed. Therefore, deterioration of reception sensitivity ofreception paths AR to DR can be suppressed, and deterioration of signalquality of transmission signals output from radio frequency module 1Acan be suppressed.

In radio frequency module 1A according to this working example, it isdesirable that the first circuit component be, in particular, (4) anyone of reception filters 61R to 64R or any one of duplexers 61 to 64described above. This is because reception filters 61R to 64R andduplexers 61 to 64 have pass characteristics that deteriorate easily dueto digital control signals.

It should be noted that it is desirable that module board 91 have amultilayer structure in which a plurality of dielectric layers arestacked, and that a ground electrode pattern is formed in at least oneof the dielectric layers. Accordingly, the electromagnetic shieldingfunction of module board 91 is improved.

Furthermore, in radio frequency module 1A according to this workingexample, a plurality of external-connection terminals 150 are disposedon the principal surface 91 b-side of module board 91.

Antenna connection terminal 100 is configured using one ofexternal-connection terminals 150, and is formed on principal surface 91b, at a position next to duplexer 60. According to this arrangement, thelength of the line connecting antenna connection terminal 100 andduplexer 60 can be shortened, and thus transfer loss of transmissionsignals transferred in radio frequency module 1A can be reduced.

Furthermore, transmission input terminals 111 and 112 are configuredusing two of external-connection terminals 150, and are formed atpositions overlapping transmission power amplifiers 11 and 12, on theother side of module board 91. According to this arrangement, the lengthof the line connecting transmission input terminal 111 and transmissionpower amplifier 11 can be shortened and the length of the lineconnecting transmission input terminal 112 and transmission poweramplifier 12 can be shortened, and thus transfer loss of transmissionsignals transferred in radio frequency module 1A can be reduced.

Furthermore, reception output terminals 121 and 122 are configured usingtwo of external-connection terminals 150, and are formed on principalsurface 91 b at positions next to reception low-noise amplifiers 21 and22. According to this arrangement, the length of the line connectingreception output terminal 121 and reception low-noise amplifier 21 canbe shortened and the length of the line connecting reception outputterminal 122 and reception low-noise amplifier 22 can be shortened, andthus transfer loss of reception signals transferred in radio frequencymodule 1A can be reduced

Furthermore, radio frequency module 1A exchanges electrical signals withthe mother board disposed on the z-axis negative direction-side of radiofrequency module 1A, via external-connection terminals 150. Furthermore,some external-connection terminals 150 are set to the ground potentialof the mother board. Since reception low-noise amplifiers 21 and 22 andswitches 53, 54, and 55 for which profile reduction is readilyachievable are disposed on principal surface 91 b which faces the motherboard, out of principal surfaces 91 a and 91 b, and transmission poweramplifiers 11 and 12 for which profile reduction is not readilyachievable are not disposed on principal surface 91 b, profile reductionof radio frequency module 1A as a whole can be achieved.

As illustrated in FIG. 2A and FIG. 2B, external-connection terminals 150may be columnar electrodes penetrating through resin material 93 in thez-axis direction, and may be bump electrodes formed on principal surface91 b. When external-connection terminals 150 are bump electrodes, resinmaterial 93 on the principal surface 91 b-side need not be included.

Furthermore, as illustrated in (b) in FIG. 2A, in radio frequency module1A according to this working example, in a plan view of module board 91,external-connection terminals 150 g which are set to the groundpotential may be disposed between (i) reception low-noise amplifiers 21and 22 and (ii) PA control circuit 13 which are disposed on principalsurface 91 b.

Accordingly, even when PA control circuit 13 and reception low-noiseamplifiers 21 and 22 are disposed on principal surface 91 b, PA controlcircuit 13 and reception low-noise amplifiers 21 and 22 are disposedwith external-connection terminals 150 g interposed therebetween.Accordingly, electric field coupling, magnetic field coupling, orelectromagnetic field coupling of PA control circuit 13 and receptionlow-noise amplifiers 21 and 22 can be suppressed. For this reason, it ispossible to further prevent digital noise output from PA control circuit13 from flowing into reception paths AR to DR. Therefore, it is possibleto further prevent the digital noise from flowing into any of receptionpaths AR to DR and causing reception sensitivity to deteriorate.

Furthermore, in radio frequency module 1A according to this workingexample, PA control circuit 13 is disposed on principal surface 91 b andis connected to external-connection terminal 150 d. External-connectionterminal 150 d is connected to RFIC 3 disposed on the z-axis negativedirection-side, and conveys the digital control signals output from RFIC3 to PA control circuit 13. For this reason, the aforementioned digitalcontrol signals do not reach the principal surface 91 a-side, and thusdigital noise caused by the digital control signals can be kept only onthe principal surface 91 b-side. Therefore, it is possible to preventthe digital noise caused by the digital control signals from flowinginto radio frequency module 1A.

Furthermore, in radio frequency module 1A according to this workingexample, transmission power amplifiers 11 and 12 are disposed onprincipal surface 91 a.

Among the circuit components included in radio frequency module 1A,transmission power amplifiers 11 and 12 are components that generate alarge amount of heat. To improve the heat dissipation of radio frequencymodule 1A, it is important to dissipate the heat generated bytransmission power amplifiers 11 and 12 to the mother board, using aheat dissipation path having a small thermal resistance. If transmissionpower amplifiers 11 and 12 were disposed on principal surface 91 b, theelectrode lines connected to transmission power amplifiers 11 and 12would be disposed on principal surface 91 b. For this reason, the heatdissipation path would include a heat dissipation path that passesthrough only the planar line pattern (along the xy plane direction) onprincipal surface 91 b. This planar line pattern has a large thermalresistance due to being formed using metal thin-film. For this reason,when transmission power amplifiers 11 and 12 are disposed on principalsurface 91 b, heat dissipation deteriorates.

In contrast, when transmission power amplifiers 11 and 12 are disposedon principal surface 91 a, transmission power amplifiers 11 and 12 andexternal-connection terminal 150 can be connected via a throughelectrode penetrating between principal surface 91 a and principalsurface 91 b. Therefore, as a heat dissipation path of transmissionpower amplifiers 11 and 12, the heat dissipation path that passesthrough only the planar line pattern along the xy plane direction andhas a large thermal resistance among the lines in module board 91, canbe eliminated. Therefore, it is possible to provide a small radiofrequency module 1A in which heat dissipation from transmission poweramplifiers 11 and 12 to the mother board is improved.

Furthermore, according to the above-described configuration whichimproves the heat dissipation of radio frequency module 1A,external-connection terminals, and the like, for heat dissipation aredisposed in the region of principal surface 91 b which is located on theopposite side of transmission power amplifiers 11 and 12 in the z-axisdirection, and thus the arrangement of circuit components is restricted.On the other hand, since high power transmission signals flow in thetransmission path connecting transmission power amplifier 11 and switch51, it is desirable to shorten the transmission path as much aspossible. From this point of view, it is desirable for transmissionpower amplifier 11 and switch 51 to be disposed opposite each other withmodule board 91 interposed therebetween. However, due to theaforementioned restriction, it is difficult to dispose transmissionpower amplifier 11 and switch 51 opposite each other. Therefore, it isdesirable that switch 51 be disposed on principal surface 91 a on whichtransmission power amplifier 11 is disposed, so as to be next totransmission power amplifier 11.

It should be noted that reception low-noise amplifiers 21 and andswitches 53, 54, and 55 may be built into a single semiconductor IC 10.Accordingly, the z-axis direction height of principal surface 91 b canbe reduced, and the component mounting area of principal surface 91 bcan be reduced. Therefore, radio frequency module 1A can beminiaturized. In addition, semiconductor IC 10 may include PA controlcircuit 13.

Furthermore, it is desirable that, in a plan view of module board 91,switches 53 and 54 disposed on principal surface 91 b and transmissionpower amplifiers 11 and 12 disposed on principal surface 91 a do notoverlap, and switches 51 and 52 disposed on principal surface 91 a andswitches 53 and 54 disposed on principal surface 91 b do not overlap.

Accordingly, aside from (i) switches 53 and 54 connected to thereception paths and (ii) transmission power amplifiers 11 and 12 beingdisposed with module board 91 interposed therebetween, it is alsopossible to ensure sufficient distance between switches 53 and 54 andtransmission power amplifiers 11 and 12. Furthermore, aside from (i)switches 53 and 54 connected to the reception paths and (ii) switches 51and 52 connected to the transmission path being disposed with moduleboard 91 interposed therebetween, it is also possible to ensuresufficient distance between switches 53 and 54 and switches 51 and 52.Accordingly, isolation between the transmission paths and the receptionpaths further improves, and thus it is possible to further preventtransmission signals, harmonics, and spurious waves of intermodulationdistortion from flowing into the reception paths and causingdeterioration of reception sensitivity.

Furthermore, as shown in radio frequency module 1A according to thisworking example, it is desirable that, in a plan view of module board91, the inductor of matching circuit 41 disposed on principal surface 91a and switch 53 disposed on principal surface 91 b overlap, and theinductor of matching circuit 42 disposed on principal surface 91 a andswitch 54 disposed on principal surface 91 b overlap. Accordingly, sincethe inductor of matching circuit 41 and switch 53 are located oppositeeach other via module board 91, the length of the line connecting theinductor of matching circuit 41 and switch 53 can be shortened.Furthermore, since the inductor of matching circuit 42 and switch 54 arelocated opposite each other via module board 91, the length of the lineconnecting the inductor of matching circuit 42 and switch 54 can beshortened. Therefore, transfer loss in the transmission path can bereduced.

Furthermore, as shown in radio frequency module 1A according to thisworking example, it is desirable that, in a plan view of module board91, at least one of duplexer 61 (or reception filter 61R) or 62 (orreception filter 62R) disposed on principal surface 91 a and switch 53disposed on principal surface 91 b overlap. Accordingly, since at leastone of duplexer 61 or 62 and switch 53 are located opposite each othervia module board 91, the length of the line connecting the at least oneof duplexer 61 or 62 and switch 53 can be shortened. Therefore, transferloss in the transmission path can be reduced. Furthermore, it isdesirable that at least one of duplexer 63 (or reception filter 63R) or64 (or reception filter 64R) which are disposed on principal surface 91a and switch 54 which is disposed on principal surface 91 b overlap.Accordingly, since at least one of duplexer 63 or 64 and switch 54 arelocated opposite each other via module board 91, the length of the lineconnecting the at least one of duplexer 63 or 64 and switch 54 can beshortened. Therefore, transfer loss in the transmission path can bereduced.

Furthermore, as shown in radio frequency module 1A according to thisworking example, it is desirable that, in a plan view of module board91, transmission power amplifier 11, switch 51, and duplexer 61 (ortransmission filter 61T) or 62 (or transmission filter 62T) are disposedin the stated order on principal surface 91 a. Accordingly, transmissionpower amplifier 11, switch 51, and duplexer 61 or 62 are disposed onprincipal surface 91 a in the same order as the electrical connectingorder. Accordingly, the length of the line connecting transmission poweramplifier 11, switch 51, and duplexer or 62 can be shortened. Therefore,transfer loss in the transmission path can be reduced. Furthermore, itis desirable that transmission power amplifier 12, switch 52, andduplexer 63 (or transmission filter 63T) or 64 (or transmission filter64T) are disposed in the stated order on principal surface 91 a.Accordingly, transmission power amplifier 12, switch 52, and duplexer 63or 64 are disposed on principal surface 91 a in the same order as theelectrical connecting order. Accordingly, the length of the lineconnecting transmission power amplifier 12, switch 52, and duplexer or64 can be shortened. Therefore, transfer loss in the transmission pathcan be reduced.

[3. Circuit Element Arrangement Configuration of Radio Frequency Module1C According to Working Example 1]

FIG. 2C is a schematic diagram illustrating a plan view configuration ofradio frequency module 1C according to Variation 1. It should be notedthat (a) in FIG. 2C illustrates an arrangement diagram of circuitelements in the case where principal surface 91 a of opposite principalsurfaces 91 a and 91 b of module board 91 is viewed from the z-axispositive direction-side. On the other hand, (b) in FIG. 2C illustrates asee-through view of the arrangement of circuit elements in the casewhere principal surface 91 b is viewed from the z-axis positivedirection-side.

Radio frequency module 1C according to Variation 1 specifically showsthe arrangement configuration of respective circuit elements included inradio frequency module 1 according to the embodiment.

Compared to radio frequency module 1A according to Working Example 1,radio frequency module 1C according to this variation is different inthe arrangement configuration of switch 55. Hereinafter, radio frequencymodule 1C according to this variation will be described omittingdescription of points that are the same as in radio frequency module 1Aaccording to Working Example 1 and focusing on the points that aredifferent.

As illustrated in FIG. 2C, in radio frequency module 1C according tothis variation, transmission power amplifiers 11 and 12, switches 51 and52, duplexers 61 to 64, and matching circuits 31, 32, 41, and 42 aresurface mounted on principal surface 91 a of module board 91. On theother hand, PA control circuit 13, reception low-noise amplifiers 21 and22, switches 53, 54, and 55, and diplexer 60 are surface mounted onprincipal surface 91 b of module board 91.

In this working example, PA control circuit 13 is disposed on principalsurface 91 b, and switches 51 and 52 are disposed on principal surface91 a.

According to the above-described configuration, PA control circuit 13and switches 51 and 52 are disposed with module board 91 interposedtherebetween. For this reason, it is possible to prevent a digitalcontrol signal output from PA control circuit 13 from causing thegeneration of a spurious signal in the adjacent channel of atransmission signal which passes switch 51 or 52. Accordingly,deterioration of the ACLR of the transmission signal can be suppressed.

Furthermore, in radio frequency module 1C according to this variation,reception low-noise amplifiers 21 and 22 and switches 53 to 55 can beformed in a single semiconductor IC. Since external-connection terminals150 g are disposed between this semiconductor IC and PA control circuit13, miniaturization is promoted while suppressing deterioration ofreception sensitivity.

It should be noted that, in radio frequency module 1A according toWorking Example 1 and radio frequency module 1C according Variation 1,external-connection terminals 150 may be disposed on principal surface91 a.

[4. Circuit Element Arrangement Configuration of Radio Frequency Module1B According to Working Example 2]

FIG. 3A is a schematic diagram illustrating a plan view configuration ofradio frequency module 1B according to Working Example 2. Furthermore,FIG. 3B is a schematic diagram illustrating a cross-sectionalconfiguration of radio frequency module 1B according to Working Example2, and specifically illustrates a cross-section taken along lineIIIB-IIIB in FIG. 3A. It should be noted that (a) in FIG. 3A illustratesan arrangement diagram of circuit elements in the case where principalsurface 91 a of opposite principal surfaces 91 a and 91 b of moduleboard 91 is viewed from the z-axis positive direction-side. On the otherhand, (b) in FIG. 3A illustrates a see-through view of the arrangementof circuit elements in the case where principal surface 91 b is viewedfrom the z-axis positive direction-side.

Radio frequency module 1B according to Working Example 2 specificallyshows the arrangement configuration of respective circuit elementsincluded in radio frequency module 1 according to the embodiment.

Compared to radio frequency module 1A according to Working Example 1,radio frequency module 1B according to this Working Example is differentonly in the arrangement configuration of circuit elements included inradio frequency module 1B. Hereinafter, radio frequency module 1Baccording to this working example will be described omitting descriptionof points that are the same as in radio frequency module 1A according toWorking Example 1 and focusing on the points that are different.

Module board 91 is a board having principal surface 91 a (firstprincipal surface) and principal surface 91 b (second principal surface)on opposite sides. For module board 91, for example, an LTCC boardhaving a stacked structure of a plurality of dielectric layers, an HTCCboard, a component-embedded board, a board having an RDL, a printedcircuit board, or the like can be used.

As illustrated in FIG. 3A and FIG. 3B, in radio frequency module 1Baccording to this working example, transmission power amplifiers 11 and12, PA control circuit 13, switch 55, duplexers 61 to 64, and matchingcircuits 31, 32, 41 and 42 are surface mounted on principal surface 91 aof module board 91. On the other hand, reception low-noise amplifiers 21and 22, switches 51, 52, 53, and 54, and diplexer 60 are surface mountedon principal surface 91 b of module board 91. It should be noted that,although not illustrated in FIG. 3A and FIG. 3B, matching circuits 71 to74 and coupler 80 may be surface mounted on either one of principalsurfaces 91 a or 91 b of module board 91, or may be embedded in moduleboard 91.

In this working example, PA control circuit 13 is disposed on principalsurface 91 a, and switches 51 and 52 are disposed on principal surface91 b.

According to the above-described configuration, PA control circuit 13and switches 51 and 52 are disposed with module board 91 interposedtherebetween. Accordingly, electric field coupling, magnetic fieldcoupling, or electromagnetic field coupling of PA control circuit 13 andswitches 51 and 52 can be suppressed. For this reason, it is possible toprevent a digital control signal output from PA control circuit 13 fromcausing the generation of a spurious signal in the adjacent channel of atransmission signal which passes switch 51 or 52. Accordingly,deterioration of the ACLR of the transmission signal can be suppressed.Therefore, it is possible to provide radio frequency module 1B thatsuppresses transmission signal quality deterioration.

Furthermore, although not illustrated in FIG. 3A and FIG. 3B, in a planview of module board 91, PA control circuit 13 and switch 51 may atleast partially overlap. Alternatively, in a plan view of module board91, PA control circuit 13 and switch 52 may at least partially overlap.

Accordingly, since the control line connecting PA control circuit 13 andswitch 51 or 52 can be shortened, it is possible to further prevent thedigital control signal output from PA control circuit 13 to switch 51 or52 from causing the generation of a spurious signal in the adjacentchannel of the transmission signal that passes switch 51 or 52.Accordingly, deterioration of the ACLR of the transmission signal can befurther suppressed.

In this working example, reception low-noise amplifier 21 and 22,switches 53 and 54, and diplexer 60 are first circuit componentsconnected to reception paths AR to DR, and are disposed on principalsurface 91 b. On the other hand, PA control circuit 13 is disposed onprincipal surface 91 a. In other words, PA control circuit 13 and thefirst circuit components are disposed with module board 91 interposedtherebetween.

According to this configuration, PA control circuit 13 is disposed onprincipal surface 91 a of module board 91, and the first circuitcomponents connected to reception paths AR to DR are disposed onprincipal surface 91 b. In other words, PA control circuit 13 and thefirst circuit components are disposed with module board 91 interposedtherebetween. Accordingly, electric field coupling, magnetic fieldcoupling, or electromagnetic field coupling of PA control circuit 13 andthe first circuit components can be suppressed. For this reason, it ispossible to prevent the harmonic of a digital control signal input to oroutput from PA control circuit 13 from flowing into reception paths ARto DR. Therefore, it is possible to prevent the harmonic from flowinginto any of reception paths AR to DR and causing reception sensitivityto deteriorate.

In radio frequency module 1B according to this working example, it isdesirable that diplexer 60 in particular is a first circuit component.This is because the chip inductor included in diplexer 60 is easilyaffected by control signals.

Furthermore, in radio frequency module 1B according to this workingexample, it is desirable that reception low-noise amplifier 21 or 22 inparticular is a first circuit component. Specifically, PA controlcircuit 13 is disposed on principal surface 91 a, and receptionlow-noise amplifier 21 or 22 is disposed on principal surface 91 b.

This is because deterioration of reception sensitivity is great whenreception low-noise amplifier 21 or 22 located in the back-most stage ofa reception path is affected by a digital control signal. Accordingly,electric field coupling, magnetic field coupling, or electromagneticfield coupling of PA control circuit 13 and reception low-noiseamplifiers 21 or 22 can be suppressed. For this reason, it is possibleto prevent the harmonic of a digital control signal input to or outputfrom PA control circuit 13 from flowing into reception paths AR to DRvia reception low-noise amplifier 21 or 22. Therefore, it is possible toprevent the harmonic from flowing into any of reception paths AR to DRand causing reception sensitivity to deteriorate.

It should be noted that reception low-noise amplifiers 21 and 22 andswitches 53 and 54 may be included in a single semiconductor IC. Inaddition, the semiconductor IC may include switches 51 and 52.Accordingly, radio frequency module 1B can be further miniaturized.

Furthermore, as illustrated in FIG. 3A, it is desirable that, in a planview of module board 91, PA control circuit 13 and the first circuitcomponents connected to reception paths AR to DR do not overlap.Accordingly, aside from PA control circuit 13 and the first circuitcomponents being disposed with module board 91 interposed therebetween,it is possible to ensure sufficient distance between PA control circuit13 and the first circuit components, and thus electric field coupling,magnetic field coupling, or electromagnetic field coupling of PA controlcircuit 13 and the first circuit components can be further suppressed.

It should be noted that it is desirable that module board 91 have amultilayer structure in which a plurality of dielectric layers arestacked, and that a ground electrode pattern is formed in at least oneof the dielectric layers. Accordingly, the electromagnetic shieldingfunction of module board 91 is further improved.

Furthermore, in radio frequency module 1B according to this workingexample, a plurality of external-connection terminals 150 are disposedon the principal surface 91 b-side of module board 91. Radio frequencymodule 1B exchanges electrical signals with the mother board disposed onthe z-axis negative direction-side of radio frequency module 1B, viaexternal-connection terminals 150. Furthermore, some external-connectionterminals 150 are set to the ground potential of the mother board. Sincereception low-noise amplifiers 21 and 22, switches 51 to 54, anddiplexer 60 for which profile reduction is readily achievable aredisposed on principal surface 91 b which faces the mother board, out ofprincipal surfaces 91 a and 91 b, and transmission power amplifiers 11and 12 for which profile reduction is not readily achievable are notdisposed on principal surface 91 b, profile reduction of radio frequencymodule 1B as a whole can be achieved.

Furthermore, in radio frequency module 1B according to this workingexample, in a plan view of module board 91, transmission power amplifier11 and matching circuits 31 and 32 are disposed between (i) PA controlcircuit 13 and (ii) duplexers 61 to 64 and matching circuits 41 and 42which are connected to the reception paths. It should be noted that thecomponents that are disposed between PA control circuit 13 and duplexers61 to 64 and matching circuits 41 and 42 which are connected to thereception paths need not be transmission power amplifier 11 and matchingcircuits 31 and as long as they are conductive components. Moreover, aconductive component is an electronic component including a conductivemember such as a signal extraction electrode, and is for example any oneof a chip resistor, a chip capacitor, a chip inductor, a filter, aswitch, or an active element such as an amplifier and a control circuit.

Accordingly, even when PA control circuit 13, duplexers 61 to 64, andmatching circuits 41 and 42 are disposed on principal surface 91 a,electric field coupling, magnetic field coupling, or electromagneticfield coupling of (i) PA control circuit 13 and (ii) duplexers 61 to 64and matching circuits 41 and 42 can be suppressed. For this reason, itis possible to further prevent the harmonic of a digital control signalinput to or output from PA control circuit 13 from flowing intoreception paths AR to DR. Therefore, it is possible to further preventthe harmonic from flowing into any of reception paths AR to DR andcausing reception sensitivity to deteriorate.

Furthermore, in radio frequency module 1B according to this workingexample, transmission power amplifiers 11 and 12 are disposed onprincipal surface 91 a.

Accordingly, as a heat dissipation path of transmission power amplifiers11 and 12, the heat dissipation path that passes through only the planarline pattern along the xy plane direction and has a large thermalresistance among the lines in module board 91, can be eliminated.Therefore, it is possible to provide a small radio frequency module 1Bin which heat dissipation from transmission power amplifiers 11 and 12to the mother board is improved.

Furthermore, as shown in radio frequency module 1B according to thisworking example, it is desirable that, in a plan view of module board91, at least one of duplexer 61 (or reception filter 61R) or 62 (orreception filter 62R) disposed on principal surface 91 a and switch 53disposed on principal surface 91 b overlap. Accordingly, since at leastone of duplexer 61 or 62 and switch 53 are located opposite each othervia module board 91, the length of the line connecting the at least oneof duplexer 61 or 62 and switch 53 can be shortened. Therefore, transferloss in the transmission path can be reduced. Furthermore, it isdesirable that at least one of duplexer 63 (or reception filter 63R) or64 (or reception filter 64R) which are disposed on principal surface 91a and switch 54 which is disposed on principal surface 91 b overlap.Accordingly, since at least one of duplexer 63 or 64 and switch 54 arelocated opposite each other via module board 91, the length of the lineconnecting the at least one of duplexer 63 or 64 and switch 54 can beshortened. Therefore, transfer loss in the transmission path can bereduced.

It should be noted that, in radio frequency module 1B according toWorking Example 2, external-connection terminals 150 may be disposed onprincipal surface 91 a.

[5. Advantageous Effects, and so On]

As described above, radio frequency module 1A according to WorkingExample 1 includes module board 91 including principal surface 91 a andprincipal surface 91 b on opposite sides thereof; transmission poweramplifier 11; PA control circuit 13 that controls transmission poweramplifier 11; transmission filters 61T and 62T; and switch 51 configuredto switch connection of the output terminal of transmission poweramplifier 11 between transmission filter 61T and transmission filter62T. PA control circuit 13 is disposed on principal surface 91 b, andswitch 51 is disposed on principal surface 91 a

According to the above-described configuration, PA control circuit 13and switch 51 are disposed with module board 91 interposed therebetween.Accordingly, electric field coupling, magnetic field coupling, orelectromagnetic field coupling of PA control circuit 13 and switch 51can be suppressed. For this reason, it is possible to prevent a digitalcontrol signal output from PA control circuit 13 from causing thegeneration of a spurious signal in the adjacent channel of atransmission signal which passes switch 51. Accordingly, deteriorationof the ACLR of the transmission signal can be suppressed. Therefore, itis possible to provide radio frequency module 1A that suppressestransmission signal quality deterioration.

Furthermore, in radio frequency module 1A, in a plan view of moduleboard 91, PA control circuit 13 and switch 51 may at least partiallyoverlap.

PA control circuit 13 controls transmission amplifier 11, and controlsconnection and disconnection of switch 51 by using digital controlsignals. According to the above-described configuration, since PAcontrol circuit 13 and switch 51 partially overlap in the aforementionedplan view, the control lines connecting PA control circuit 13 and switch51 can be shortened. Accordingly, it is possible to further prevent thecontrol signal output from PA control circuit 13 to switch 51 fromcausing the generation of a spurious signal in the adjacent channel ofthe transmission signal that passes switch 51. Accordingly,deterioration of the ACLR of the transmission signal can be furthersuppressed.

Furthermore, radio frequency module 1A may further includeexternal-connection terminals 150, and external-connection terminals 150may be disposed on principal surface 91 b.

Accordingly, PA control circuit 13 disposed on principal surface 91 breceives digital control signals from the mother board-side, viaexternal-connection terminals 150. For this reason, the aforementioneddigital control signals do not reach the principal surface 91 a-side,and thus digital noise caused by the digital control signals can be keptonly on the principal surface 91 b-side. Therefore, it is possible toprevent the digital noise caused by the digital control signals fromflowing into radio frequency module 1.

Furthermore, radio frequency module 1A may include reception low-noiseamplifier 21. Reception low-noise amplifier 21 may be disposed onprincipal surface 91 b. In a plan view of module board 91,external-connection terminals 150 g, which are set to a groundpotential, may be interposed between PA control circuit 13 and receptionlow-noise amplifier 21.

Accordingly, electric field coupling, magnetic field coupling, orelectromagnetic field coupling of PA control circuit 13 and receptionlow-noise amplifier 21 can be suppressed. For this reason, it ispossible to further prevent the harmonic of a digital control signalinput to or output from PA control circuit 13 from flowing intoreception paths AR and BR. Therefore, it is possible to further preventthe harmonic from flowing into either reception path AR or BR andcausing reception sensitivity to deteriorate.

Furthermore, in radio frequency module 1A, transmission power amplifier11 may be disposed on principal surface 91 a.

Therefore, as a heat dissipation path of transmission power amplifier11, the heat dissipation path that passes through only the planar linepattern and has a large thermal resistance among the lines in moduleboard 91 can be eliminated. Therefore, it is possible to provide a smallradio frequency module 1A in which heat dissipation from transmissionpower amplifier 11 to the mother board is improved.

Furthermore, radio frequency module 1B may include external-connectionterminals 150. External-connection terminals 150 may be disposed onprincipal surface 91 b, PA control circuit 13 may be disposed onprincipal surface 91 a, and switch 51 may be disposed on principalsurface 91 b.

According to the above-described configuration, PA control circuit 13and switch 51 are disposed with module board 91 interposed therebetween.Accordingly, electric field coupling, magnetic field coupling, orelectromagnetic field coupling of PA control circuit 13 and switch 51can be suppressed. Accordingly, deterioration of the ACLR of thetransmission signal can be suppressed. Therefore, it is possible toprovide radio frequency module 1B that suppresses transmission signalquality deterioration.

Furthermore, radio frequency module 1B may include reception low-noiseamplifier 21, and reception low-noise amplifier 21 may be disposed onprincipal surface 91 b.

Accordingly, electric field coupling, magnetic field coupling, orelectromagnetic field coupling of PA control circuit 13 and receptionlow-noise amplifier 21 can be suppressed. For this reason, it ispossible to prevent the harmonic of a digital control signal input to oroutput from PA control circuit 13 from flowing into reception paths ARand BR via reception low-noise amplifier 21. Therefore, it is possibleto prevent the harmonic from flowing into either of reception path AR orBR and causing reception sensitivity to deteriorate.

Furthermore, communication device 5 includes antenna 2, RFIC 3 thatprocesses a radio frequency signal which is to be transmitted or hasbeen received by antenna 2, and radio frequency circuit 1 that transfersthe radio frequency signal between antenna 2 and RFIC 3.

Accordingly, it is possible to provide communication device 5 thatsuppresses transmission signal quality deterioration.

OTHER EMBODIMENTS

Although a radio frequency module and communication device according tothe present disclosure have been described above based on an exemplaryembodiment and working examples thereof, the radio frequency circuit andcommunication device according to the present disclosure are not limitedto the foregoing embodiment and working examples. The present inventionalso encompasses other embodiments achieved by combining arbitraryelements in the above embodiment and working example thereof, variationsresulting from various modifications to the embodiment and workingexample thereof that may be conceived by those skilled in the artwithout departing from the essence of the present disclosure, andvarious devices that include the radio frequency module andcommunication device according to the present disclosure.

Furthermore, for example, in the radio frequency module andcommunication device according to the foregoing embodiment and theworking example thereof, another circuit element and line may beinserted in a path connecting respective circuit elements and signalpaths disclosed in the drawings.

INDUSTRIAL APPLICABILITY

The present disclosure can be widely used in communication apparatusessuch as a mobile phone, as a radio frequency module provided in amultiband-compatible front-end unit.

The invention claimed is:
 1. A radio frequency module, comprising: a module board including a first principal surface and a second principal surface on opposite sides of the module board; a transmission power amplifier disposed on the module board; a control circuit configured to control the transmission power amplifier; a first transmission filter and a second transmission filter; and a first switch configured to switch connection of an output terminal of the transmission power amplifier between the first transmission filter and the second transmission filter, wherein the control circuit is disposed on the first principal surface, and the first switch is disposed on the second principal surface.
 2. The radio frequency module according to claim 1, wherein in a plan view of the module board, the control circuit and the first switch at least partially overlap.
 3. The radio frequency module according to claim 1, further comprising: one or more external-connection terminals, wherein the one or more external-connection terminals are disposed on the first principal surface.
 4. The radio frequency module according to claim 3, further comprising: a reception low-noise amplifier, wherein the reception low-noise amplifier is disposed on the first principal surface, and in a plan view of the module board, at least one of the one or more external-connection terminals is interposed between the control circuit and the reception low-noise amplifier, the at least one of the one or more external-connection terminals being set to a ground potential.
 5. The radio frequency module according to claim 3, wherein the transmission power amplifier is disposed on the second principal surface.
 6. The radio frequency module according to claim 1, further comprising: one or more external-connection terminals, wherein the one or more external-connection terminals are disposed on the second principal surface.
 7. The radio frequency module according to claim 6, further comprising: a reception low-noise amplifier, wherein the reception low-noise amplifier is disposed on the second principal surface.
 8. The radio frequency module according to claim 6, wherein the transmission power amplifier is disposed on the first principal surface.
 9. A communication device, comprising: an antenna; an RF signal processing circuit configured to process a radio frequency signal which is to be transmitted or has been received by the antenna; and a radio frequency module configured to transfer the radio frequency signal between the antenna and the RF signal processing circuit, the radio-frequency module including a module board including a first principal surface and a second principal surface on opposite sides of the module board, a transmission power amplifier disposed on the module board, a control circuit configured to control the transmission power amplifier, a first transmission filter and a second transmission filter, and a first switch configured to switch connection of an output terminal of the transmission power amplifier between the first transmission filter and the second transmission filter, wherein the control circuit is disposed on the first principal surface, and the first switch is disposed on the second principal surface.
 10. The communication device according to claim 9, wherein in a plan view of the module board, the control circuit and the first switch at least partially overlap.
 11. The communication device according to claim 9, further comprising: one or more external-connection terminals, wherein the one or more external-connection terminals are disposed on the first principal surface.
 12. The communication device according to claim 11, further comprising: a reception low-noise amplifier, wherein the reception low-noise amplifier is disposed on the first principal surface, and in a plan view of the module board, at least one of the one or more external-connection terminals is interposed between the control circuit and the reception low-noise amplifier, the at least one of the one or more external-connection terminals being set to a ground potential.
 13. The communication device according to claim 11, wherein the transmission power amplifier is disposed on the second principal surface.
 14. The communication device according to claim 9, further comprising: one or more external-connection terminals, wherein the one or more external-connection terminals are disposed on the second principal surface.
 15. The communication device according to claim 14, further comprising: a reception low-noise amplifier, wherein the reception low-noise amplifier is disposed on the second principal surface.
 16. The communication device according to claim 14, wherein the transmission power amplifier is disposed on the first principal surface. 